The temple was built by the royal queen Kanakawati to commemorate her son Jagat Singh. She wanted the temple to be a universally renowned temple and hence the nomenclature “ Jagat SinghMani” i.e. Head Jewel of the idol of Lord Vishnu.
The temple belongs to the Vaishnava cult of Hindus .It is universally worshipped.
The south Indian style of temple architecture has been used. The temple was to lie a universally renowned temple and hence the menenclature " Jagat Singh Mani" i.e. Head Jewel of the idol of Lord Vishnu.
The white idol of Vishnu is there in the shrine. An idol of Lord Krishna is also there Mira Bai the renewed devotee used to worship this idol here. This is idol called Mira Mandir.
At the entrance gate we find a beautifully ornamental toran or bracketing. Nearby in a canopy these is idol of Garudji, The vehicle of Lord Vishnu. More that eleven lac rupees were spent on construction of this temple.
The above text courtesy from the website of http://devasthan.rajasthan.gov.in/images/Jaipur/jagatshiromani.htm
In my collection i have one vintage black and white post card of this Jagat Shiromani Temple Amer.